Canon Kabushiki Kaisha

Eriko Saito

Mayumi Yamamoto

Mikio Sanada

Yoshihisa Takizawa

Akira Nagashima

Keiichi Murai

Kumiko Mafune

Ryuji Katsuragi

Hiromitsu Hirabayashi

Shinichi Sato

Toshiharu Inui

Masaya Uetsuki

Fumihiro Gotoh

Miyuki Fujita

Yoshifumi Hattori

Tsuyoshi Eida

Takao Yamamoto

Hisashi Teraoka

Osamu Nishiwaki

Masahiko Tonogaki

When a black image region is printed, the overall pixels in the region is printed by a black ink. Then, a cation type cyan ink which makes a coloring agent in the ink insoluble is printed on the pixels of a predetermined pattern. By this, the dye of the black ink is maintained near the surface of the printing medium to increase density of the black image. At the same time, for preventing variation of tone of the black image, the pixels of the predetermined pattern are printed by a yellow ink.

Method and apparatus for ink-jet printing

Disclosed herein is an ink set comprising in combination at least two inks of different colors, wherein at least one ink comprises a cationic dye and an amphoteric compound, and another ink of a color different from said one ink comprises an anionic dye and a water-soluble anionic polymer or nonionic polymer in addition to the dye.

Ink set and ink-jet recording method using the same

Disclosed herein is a yellow ink comprising at least two yellow dyes and a liquid medium dissolving or dispersing the dyes therein, wherein the ink comprises a dye represented by the following general formula (1) in the state of a free acid, and a yellow dye having a SO.sub.3 H group as a main solubilizing group in the state of a free acid and having its position in the L*a*b* chromaticity diagram at b*=xa* (3.ltoreq.x.ltoreq..infin.): ##STR1##

Ink, and ink-jet recording method and instruments using the same

Disclosed herein is an ink-jet ink comprising in combination at least one compound selected from nitrogen compounds consisting of secondary amines and derivatives thereof, tertiary amines and derivative thereof, and complexes thereof and having at least one group selected from the group consisting of alkyl groups, a carboxyl group and the salts thereof, and a sulfonic group and the salts thereof, and a cyclic phosphate in a liquid medium in which a dye is dissolved or dispersed.

Ink-jet ink

Disclosed herein is an ink comprising a coloring material and a liquid medium dissolving the coloring material therein, wherein the ink comprises a dye having at least one ammonium ion as a counter ion and an ammonium salt of an inorganic or organic acid.

Ink, and ink-jet recording method and instrument using the same

Growing community of inventors

Fujisawa, Japan

Eriko Saito